Illumination assembly with in-field micro devices

Abstract

An illumination assembly includes a transparent substrate and a plurality of micro devices. The transparent substrate includes a first surface and a second surface opposite the first surface. The first surface includes a viewing region through which light passes prior to reaching an eyebox. The plurality of micro devices are coupled to respective conductive pathways that are affixed to the first surface. The plurality of micro devices including at least one micro device that is positioned within the viewing region. In some embodiments, the conductive pathways are arranged in a pseudo random manner. In some instances, the viewing region is composed of a circuity free region that is circumscribed by an outer region, and the plurality of micro devices are coupled to respective conductive pathways that are affixed to the first surface in the outer region.

What is claimed is: 
     
       1. An assembly comprising:
 a transparent substrate including a first surface and a second surface opposite the first surface, the first surface including a viewing region through which light passes prior to reaching an eyebox; and 
 a plurality of micro-devices coupled to respective conductive pathways that are affixed to the first surface, the respective conductive pathways arranged in a pseudo random manner that mitigates visibility of the conductive pathways by mimicking a vasculature of a human eye, wherein the plurality of micro-devices include at least one micro-device that is positioned within the viewing region and the pseudo random manner is governed by one or more parameters, the one or more parameters including a minimum distance between adjacent conductive pathways. 
 
     
     
       2. The assembly of  claim 1 , wherein the plurality of micro-devices include at least a plurality of sources. 
     
     
       3. The assembly of  claim 2 , wherein the viewing region is composed of a circuitry free region that is circumscribed by an outer region, and the plurality of sources and the conductive pathways are located in the outer region. 
     
     
       4. The assembly of  claim 3 , wherein the assembly is part of a head-mounted display (HMD) and the circuitry free region is associated with a center region of a field of view of the HMD. 
     
     
       5. The assembly of  claim 3 , wherein the circuitry free region has a diameter of at most 12 mm. 
     
     
       6. The assembly of  claim 3 , wherein the pseudo random manner is such that there is at least 1 mm between adjacent conductive pathways that are coupled to different sources of the plurality of sources. 
     
     
       7. The assembly of  claim 3 , wherein at least one source of the plurality of sources is positioned outside the viewing region. 
     
     
       8. The assembly of  claim 3 , wherein at least one of the plurality of sources is a vertical cavity emitting laser (VCSEL). 
     
     
       9. The assembly of  claim 3 , wherein the plurality of sources are configured to emit light having a wavelength in a near-infrared range. 
     
     
       10. The assembly of  claim 1 , wherein the one or more parameters further include one or more of: a period of a conductive pathway, an amplitude of the conductive pathway, a change in curvature of the conductive pathway, and a randomness metric of the conductive pathway. 
     
     
       11. The assembly of  claim 1 , wherein at least one of the conductive pathways is transparent in a visible band of light and overlaps the viewing region. 
     
     
       12. The assembly of  claim 1 , wherein at least one of the conductive pathways is opaque in a visible band of light and is outside the viewing region. 
     
     
       13. The assembly of  claim 1 , further comprising a coating layer that is transparent in a visible band, the coating layer at least partially enclosing at least some of the plurality of micro-devices and the transparent substrate. 
     
     
       14. An assembly comprising:
 a transparent substrate including a first surface and a second surface opposite the first surface, the first surface including a viewing region through which light passes prior to reaching an eyebox, wherein the viewing region is composed of a circuitry free region that is circumscribed by an outer region; and 
 a plurality of sources coupled to respective conductive pathways that are affixed to the first surface in the outer region, the respective conductive pathways arranged in a pseudo random manner that mitigates visibility of the conductive pathways by mimicking a vasculature of a human eye, wherein the pseudo random manner is governed by one or more parameters, the one or more parameters including a minimum distance between adjacent conductive pathways. 
 
     
     
       15. The assembly of  claim 14 , wherein the circuitry free region is associated with a center region of a field of view of a head-mounted display. 
     
     
       16. The assembly of  claim 14 , wherein the circuitry free region has a diameter of at most 12 mm. 
     
     
       17. The assembly of  claim 14 , wherein at least a portion of the conductive pathways are straight. 
     
     
       18. The assembly of  claim 14 , wherein at least a portion of the conductive pathways are curved. 
     
     
       19. A near-eye display (NED), comprising:
 an assembly comprising:
 a transparent substrate including a first surface and a second surface opposite the first surface, the first surface including a viewing region through which light passes prior to reaching an eyebox, 
 a plurality of sources coupled to respective conductive pathways that are affixed to the first surface, the respective conductive pathways arranged in a pseudo random manner that mitigates visibility of the conductive pathways by mimicking a vasculature of a human eye, wherein the plurality of sources include at least one source that is positioned within the viewing region and the pseudo random manner is governed by one or more parameters, the one or more parameters including a minimum distance between adjacent conductive pathways; and 
 
 an eye tracking system comprising:
 a camera assembly configured to record light emitted by the plurality of sources and reflected by an eye positioned at the eyebox.